In order to analyze and design digital systems, one requires a solid foundation in hardware concepts. M. Morris Mano presents the necessary information in this introduction to the principles of computer hardware organization and design.
This was a textbook used in a couple of my EE digital-design classes in college, and continues to be my go-to book when researching principles of hardware design. It covers the full range of topics starting with the fundamentals of logic, and expands upon them until reaching CPU design and full system organization. Great book.